The present invention relates to illumination for theatrical, architectural and stage lighting systems.
Longer life and more energy efficient sources of light have become increasingly important thus making alternative light sources important. Recent advances in light emitting diode (LED) technology particularly the development of multi-chip and multi-LED arrays have led to brighter LEDs available in different colors. LEDs are available in both visible colors and infrared. In addition to red, yellow, green, and amber-orange, which were the first available colors, LEDs are now available in blue and even white light. LEDs operate at lower currents and yet produce 100 percent color intensity and light energy. For many applications, LEDs can compete directly with incandescent filament light sources.
LEDs emit a focused beam of color light in a variety of different angles, in contrast to incandescent filament lamps, which emit only the full spectrum of light. In order to obtain color from an incandescent filament lamp, a specific color gel or filter in the desired color spectrum must be used. Such a system results in 90 percent or more of the light energy wasted by the incandescent filament lamp. LEDs on the other hand deliver 100 percent of their energy as light and so produce a more intense colored light. White light is also produced more advantageously by LEDs. White light is obtained from LEDs in two ways: first, by using special white light LEDs; and second, by using an additive mixture of red, green and blue (RGB) LEDs at the same intensity level so as to produce a white light. With regard to the second method, variable intensity combinations of RGB LEDs will give the full color spectrum with 100 percent color intensity and light output energy. The primary colors red, green, and blue of RGB LEDs can be mixed to produce the secondary colors cyan, yellow, magenta (CYM) and also white light. Mixing green and blue gives cyan, as is known in the art of colors. Likewise as is known in the art, mixing green and red gives yellow. Mixing red and blue gives magenta. Mixing red, green, and blue together results in white. Advances in light-emitting diode technology include the development of multi-chip and multi-LED arrays, which have led to brighter LEDs available in different colors. LEDs are available in both visible colors and infrared.
LEDs are more energy efficient as well. They use only a fraction of the power required by conventional incandescent filament lamps. The solid state design of LEDs results in great durability and robustness to withstand shock, vibration, frequent power cycling, and extreme temperatures. LEDs have a typical 100,000 hours or more usable life when they are operated within their electrical specifications. Incandescent filament lamps are capable of generating high-intensity light for only a relatively short period of time and in addition are very susceptible to damage from both shock and vibration.
Incandescent filament lamps of the MR and PAR type are the best known and most widely used technologies of the architectural, theatrical and stage lighting industry. Such lamps are available in different beam angles, producing beam angles ranging from narrow spot lights to wide flood focuses. Such types of lamps are very popular because they have long-rated lives up to 5,000 hours.
Light emitting diode LED technology including white light and full color red, green, blue (RGB) tile array modules have become common in certain areas of illumination, most commonly for large scale lighted billboard displays. Such LED light sources incorporate sturdy, fast-moving and animated graphics with full color. Such flat displays offer only one fixed viewing angle, usually at 100 degrees.
Another use of fixed flat panels for LED arrays are currently used in traffic lights and for stop lights and warning hazard lights mounted on the rear of automobiles.
A recent advance in LED lamp technology has been ICOLOR (a registered trademark of Color Kinetics Inc., 10 Milk Street, Boston, Mass. 02108) MR light sources introduced by such company, and the ICOLOR MR light source is a digital color-changing lamp, which plugs into standard MR 16 type lighting fixtures. This lamp has the advantage of using variable intensity colored LEDS with a long-life of 100,000 hours or more. On the other hand, it has a fixed LED array that is limited to a fixed beam angle of 22 degrees (SPOT). Similarly, Boca Flashes, Inc. offers a compact LED array of up to 24 LEDS in a typical dichroic coated glass reflector. The beam angle is limited to 20xc2x0.
Another LED light source is use today takes the form of a flashing warning beacon. The LEDs are arranged in a cylindrical array around the circumference of a tube base. This configuration allows for viewing from a 360 degree angle. The same configuration is also used in wedge base type LED lamps as well as in LED bulbs mounted on a standard screw base.
MR and PAR type incandescent filament lamps are able to be controlled to produce complete control of output beam angles. MR and PAR lamps are fixed focus and are not adapted to control beam angles. LED technology to date does not offer complete control of output beam angles.
Some patents that have addressed this problem are as follows:
1) U.S. Pat. No. 5,752,766 issued to Bailey et al. on May 19, 1998, discloses a focusable lighting apparatus for illuminating area for visual display. A flexible base member, shown in this patent as a cylindrical base member 20, is supported on a housing and an array of LEDs 22 are supported on the flexible base member. An actuator connected to the base member is operable to move the flexible base member to selected working positions so as to direct LED generated light beams normally, inwardly or outwardly. The LEDs are supported on the flexible base 20. Base 20 can be deflected (see col. 3, lines 45-49 and also col. 4, lines 43-46) so that the optical axes 39a in a parallel mode is made to provide converging light beams indicated by the three lines 39b shown in FIG. 2 thereof, and the bending of flexible base 20 is accomplished by actuator 28 by way of a rod 26 with the second flexed position shown in phantom. It is apparent that the range of beam angles that can be achieved by pulling or pushing flexible base member 20 is limited by the unitary structure of base member 20. Base member 20 itself is described as flexible so that stretching of base member 20 itself is necessary to change the diode beam angles. The material composition of flexible member 20 is described as being made of any of various polymer or elastomer materials (col. 4, lines 51-62). The unitary structure of base 20 creates a built-in limitation position (col. 4, lines 53-62. The invention described therein has a limitation to its usefulness in the field of stage and theatrical lighting. It is also noted that the limited strength of elastomer base 20 itself to maintain constant diode beam angles is compromised so that the beam angles are significantly misdirected since the diodes 20 cannot maintain constant angles relative to the plane of flexible member 20 because flexible member 20 itself undergoes a warping effect and so maintains no constant plane angle except in the parallel beam mode. Also, the number of diodes 22 that can be mounted to base member 20 is limited by the xe2x80x9crelatively thinxe2x80x9d (col. 2, line 59) base member 20. Also, permanent molding of the light emitting elements seems necessary, which indicates a difficulty in replacing the elements when they fail.
2) U.S. Pat. No. 5,580,163 issued to Johnson on Dec. 3, 1996, discloses a plurality of light emitting elements including light bulbs and LEDs attached to a circular flexible membrane that in turn is connected to outer and inner housing that are movable relative to one another so as to flex the membrane in a predetermined manner. The inner housing is threaded into an adjusting nut that can be rotated to move the inner housing relative to the outer housing. The light emitting elements are correspondingly moved so that their collective light beams are selectively focused at a common area. In this invention, the mounting of the light emitting elements is restricted to a circular membrane. It is apparent that the number of light emitting elements are restricted. FIG. 6 of Johnson shows an increased number of light emitting elements but again this view emphasizes the limitation of lighting elements available on this device. The number of elements is limited primarily by the fact that the flexible membrane can support a restricted number of light emitting elements just as a weight bearing problem. It is further noted that because of the flexibility of the membrane holding the light emitting elements, each element will to some degree be significantly misdirected because of the warping effect of the flexible membrane as it is moved between positions. Also permanent molding of the light emitting elements are discussed, which indicates a difficulty in replacing the elements when they fail.
3) U.S. Pat. No. 5,101,326 issued to Roney on Mar. 31, 1992, discloses a lamp for a motor vehicle that discloses a plurality of light emitting diodes positioned in sockets that direct the diode generated light beams in overlapping relationship so as to meet photometric requirements set forth by law. The diodes are not selectively movable to different focal areas.
4) U.S. Pat. No. 5,084,804 issued to Schaier on Jan. 28, 1992, discloses a wide area lamp comprising a plurality of diodes mounted on a single flexible connecting path structure than can be moved to a number of shapes as required. The diodes of the disclosed lamp are not collectively and selectively adjustable in a uniform manner for being directed to a common focal area.
It is an object of the present invention to provide a lighting system that is capable of providing a plurality of selected different light beam angles from a single LED lighting system source;
It is a further object of the present invention to provide a lighting system that is capable of selectively varying the common directional angles of a plurality of individual LED arrays arranged around a common central axis;
It is a further object of the present invention to provide a lighting system that is capable of simultaneously and selectively moving a plurality of individual LED arrays about a common central axis to as to collectively arrange the totality of LED light beams arranged on individual arrays in a plurality of directional modes including a normal parallel mode of all of the LED generated light beams, a selected converging mode of all of the LED generated light beams, and a selected diverging mode of all of the LED generated light beams.
In accordance with the above objects and others that will be disclosed in the course of the disclosure of the present invention, there is provided a diode light source system for stage, theatrical and architectural lighting that includes a plurality of separate flat panels for mounting a plurality of light emitting diodes that emit a plurality of diode light beams to a common focus area, each separate panel being mounted with a plurality of grouped diodes of the plurality of diodes, each separate panel having an outer panel portion and an inner panel portion. A housing containing the panels has a center base portion and a circular rim defining a housing aperture aligned with a circular rim plane having a rim plane center that is arranged transverse to an axis aligned with the center base portion. A first connecting means flexibly secures each outer diode panel portion to the housing rim. A screw arrangement positions the panels at a plurality of selected positions wherein each of the panels is oriented at a selected angle relative to the axis and each of the grouped diodes emit diode light beams transverse to each separate panel. A second connecting means flexibly secures each inner panel portion to the screw arrangement. The panels are flat and rigid and have both the function of holding the diodes and of being electrical circuit boards for transmitting direct electrical current to the diodes grouped on each separate panel. The screw arrangement comprises an elongated externally threaded cylinder and a correspondingly internally threaded cylindrical nut, the externally threaded cylinder, which is rotatable about the axis, being threadably mounted within the cylindrical nut. The externally threaded cylinder has the circular rim plane. The first and second flexible connecting means can each be either a biasable or flexible member or a biasable spring.
The present invention will be better understood and the objects and important features, other than those specifically set forth above, will become apparent when consideration is given to the following details and description, which when taken in conjunction with the annexed drawings, describes, illustrates, and shows preferred embodiments or modifications of the present invention and what is presently considered and believed to be the best mode of practice in the principles thereof.
Other embodiments or modifications may be suggested to those having the benefit of the teachings therein, and such other embodiments or modifications are intended to be reserved especially as they fall within the scope and spirit of the subjoined claims.